What was the purpose of dew line?

The Distant Early Warning (DEW) Line was a system of radar stations established during the Cold War to detect incoming Soviet bombers and missiles approaching North America. Its primary purpose was to provide early warning of potential aerial attacks, thereby enhancing the defense capabilities of the United States and Canada. The line extended across the Arctic, from Alaska to Greenland, and played a crucial role in North American air defense strategy during the 1950s and 1960s.